Spirally coiled paper tubing and method of making



Nov. 1, 1932. R. P. BURTON n 1,885,587

SPIRALLY COILED PAPER TUBING AND METHOD OF MAKING Filed Feb. 12, 1931 Patented Nov. l, 1932 UNITE STATES RALPH P. BURTON, F CHICAGO HEIGHTS, ILLINOIS lSPIR-ALLY COILED PAPER TUBING AND METHOD 0F MAKING Application led February 12, 1931*.

The purpose of this invention is to make spirally coiled paper tubing interiorly liquidproofed and thereby adapted to be used for the bodies of containers for liquid commercial 3 products, particularly those of the character of grease, such as lard, butter, cream and other animal oils and vegetable oils. y

The invention consists in the method and steps in the process of producing such spiral l0 tubing and the tubing produced by this method.

The drawing illustrates parts of the mechanism Which may be utilized in carrying out the method which constitutes the invention.

Figure l is an axial section of.a piece of spirally coiled tubing made in accordance with this invention.

vFigure2 is a plan view of a part of a familiar type of apparatus for ceiling paper strip into tubing, adapted to be used in carrying out the method of this invention and having an added feature suitable for operating according to the method of this invent1on.

Figure 3 is a diagrammatic view shoyving r parts of a spiral ceiling machine associated with means also familiar in the art for applying adhesive to the coiled strips.

Figure 4 is a detail sectional elevation of a part of Figure 2, section being made as indicated at the line 4-4 on Figure 2 through a part Which is added to the familiar type ceiling machine for the purpose of the method of this invention.

For the best understanding of the invenr tion, the problem of which it becomes a solution, may be first described.

This problem, as indicated, relates to the economical production of a paper container for commercial substances liquid or semiliquid for which the container must be liquidproofed to prevent waste-'of the content by leakage resulting from the liquid content soaking, saturating and penetrating the container Wall.

For preventing such leakage the container must' be at least interiorly rendered liquidproef. Two methods have been attempted and somewhat employed for rendering paper containers of the familiar type having the Serial No. 515,220.

body made from spirally coiled paper tubing, interiorly liquid-proof.

According to the first method, the containers are mechanically completed through the steps'consisting of ceiling the paper strip into a tube, cutting the tube into container lengths, and securing the bottoms to the bodies. In this condition,of open-mouthed cups or cans,-suitable liquid-proofing substance is applied to the interior of the container by s'praying the same With such liquidproofing substance, which requires to be set by drying in order to serve the purpose of rendering the container liquid-proof.

This method is quite unsatlsfactory for tWo reasons: First, it is impossible to avoid the formation of minute air bubbles in the process of spraying the liquid onto the inner surface of the container; and in the next process-of drying to set the liquid-proofing substance,fthese air bubbles are liable to burst, forming minute holes in the otherwise liquid-proof coating through which the liquid or semi-liquid content of the container gets direct access to the paper, and soon soaks through it, forming a leak at each such broken bubble.

Secondly, this method is unsatisfactory, and almost prohibitively expensive for the reason that for drying and setting the liquidproofing substance on the inner surface of the containers, the latter must be stored in a drying chamber exposed to proper drying temperature for about four hours before the liquid-proofing is sufficiently set to permit the completion of the containers by applying the covers and the necessary exterior labels and markings to fit them for the commercial use for Which they are Wanted. And when it is considered that the containers are delivered 9C at the rate of four hundred per minute from the automatic machine by which the spirally coiled tubing is produced and cut into container lengths and by which the bottoms are applied and secured, and from which they c.; are automatically delivered to the spraying apparatus andlthence to the drying chamber through which they must be automatically fed and from which they must be taken automatically after four hours travel through the 10o drying chamber to the labelling and coverapplying mechanism, it will be seen thatthe drying chamber, large enough to accommodate four hours output of the coiling, bottoming, and spraying apparatus, is a necessary part of the-complete mechanism for continuous automatic manufacture of such containers; it may be understood that the cost of accommodating and operating the organization which includes such extended drying apparatus, is prohibitive.

In the second method above referred to,'

avoiding the difficulty arising from the slow drying of the interiorly coated containers, the liquid-proofing material is applied to the paper in the strip in the process of winding it from the original` storage spool onto another spool, the strip on its way from one spool to the other receiving the coating and running thence through a suitably extended passage in which it is exposed to hot air current for drying, which causes the liquid-proofing to be well set when it reaches and is wound onto the second spool; and the second spool being mounted in the spiral coiling machine, the tube is produced by the familiar method of such machines, the inner coiled strip being coiled with its consecutive coils abutting edge to edge, and an outer coil being simultaneously formed lapping the spiral seam between the abutting edges of the inner coil. Thus the completed tube has its inner surface completely covered with the fully dried and set liquid-proofing.

This method has been found unsatisfactory because it is practically impossible to produce the paper strip with its opposite edges so perfectly parallel and perfectly rectilinear that the spiral seam between the abutting edges of the consecutive coils will be perfectly closed; and on the contrary, in the. operation of this method the opportunity -for leakage between the abutting coils is even greater than that experienced from the bursting of n bubbles of the sprayed liquid-proof coatin the `first described method: ne diiculties and defects of both these previously employed methods are avoided in the method which constitutes the present in? vention.

i In the practice of this method there is rst produced a thin paper strip liquidproofed in the manner above described'for liquid-proofing the inner coiled strip in the second above described method. This thin liquid-proofed paper strip is used as a lining for the inner/coil of the tubing and lis made a little wider than the strip which is to form the inner coil. The two strips are fed together into the coiling mandrel with the inner Wider strip next to the mandrel, and with marginal portions of .the excess width of the liquid-proofed lining strip projecting past the opposite edges of the narrower strip. Suitable adhesive is applied between the two strips in their course from the spools to the mandrel.

The marginally projectin portion of the lining strip at the edge o the two strips whose course onto the mandrel is at an acute angle to the latter, is guided for defiecting it slightly out of the plane of the contacting surfaces of the two strips and away from the axis of the mandrel just before the strips run onto the mandrel, with the effect of causing said marginal portion to be completely folded about the edge of the narrower heavier strip in the spiral advance of the strips around the mandrel. The marginal portion of the liquid-proofed lining strip at the edge of the strips, whose course onto the mandrel makes an obtuse angle with the mandrel, is permitted to take its normal course onto the mandrel and thereby becomes laid on the outer sul'- face of a marginal portion of the immediately preceding coil, and thus is fiexed past and between the abutting edges of the two coils; and in the further movement of the two coils over the convex surface of the mandrel, said marginal portion, now lapped outside the next preceding coil, and over the edge about which the first mentioned marginal portion has been folded, tends to be drawn snugly down uponthe outer surface of said next preceding coil; and by this means there is interposed in the spiral seam between the successive coils a completely liquid-proofed element which, lapping outside the one coil and inside the other coil, effects a complete and completely liquid-proofed sealing of the spiral seam throughout the entire extent of the tubing.

The customary outer coil wound vonto the mandrel simultaneously with the inner coil and its lining strip, and, as in the customary manner of producing spirally coiled paper tubing,-arranged lapping the spiral seam of the inner coil, operates to ensure the com plete sealing of the spiral seam of the inner coil by the liquid-proofed lining strip applied in the manner described.

Referring to the mechanism shown in the drawing for practicing the method above described, the customary construction of this mechanism comprises a frame partly indicated at A, a mandrel, B, mounted iixedly at one end of the frame, and having the other cnd,-the right hand end in Figure 2,-extending free, a pair of endless feeding belts. D, C, passing around driving pulleys, D1, and intermediate said driving pulleys at one side of their endless courses respectively making each a spiral turn about the mandrel for engaging the spirally wound tubing for feeding the paper strips by which it'is formed. 'i

is to constitute the liquid-proofed linin of the tube as described, and a third spool not shown) carries a paper strip, H, to constitute the outer coil ofthe paper tubing lapping the spiral seam of the inner coll.

All the parts of the mechanism as thus far described are of familiar form and construction, and the feeding belt is arranged to be operated by suitable means, not shown, for rotating the pulleys, D1.

The means for initially deflecting the marginally projecting portion of the lining strip first mentioned for causing said mar inal portion to be folded about the edge o the strip, F, as shown, consists of a slender roller, K, carried on a spindle,vK1, which may be understood to be suitably mounted on the frame for positioning said roller, as shown in Figures 2,3 and 4 extending tangentially with respect to the mandrel past the edge of the strip, F, which runs onto the mandrel at an acute angle thereto, for initially flexing the marginal portion of the strip F at that edge past the edge of the strip, G, that is, outwardly with respectl to the mandrel to cause said marginal portion to become folded fully as a binding about the edge of the strip, G, as the strips pass around the mandrel with that marginal portion at the outer side of the strip, G.

I claim:

1. The method of making tubing to form the bodies of paper containers for liquids and semi-liquids consisting in producing a liquidproofed thin paper strip and a second narrower and heavier strip to form an inner body member and spirally coiling the two strips together With adhesive between them with the marginal portions of the first mentioned strip at both lateral edges extending beyond the corresponding edges of the second strip; causing said marginal portion at one edge to be folded about the edge of the second strip and causing the opposite marginal portion to be lapped inwardly by the first mentioned edge of the adjacent coil of the spiral.

2. In the method defined in claim 1, spirally coiling a third paper strip to form an outer of two body members of the container lapping the spiral seam at the abutting edges of the second strip, simultaneously with spirally coiling said second strip and liquid-proofed lining, and applying the adhesive to one of said two body members at the surface toward the other in the longitudinal movement of the strips to tangency of the coil for spirally coiling said members together.

3. In the method defined in claim 1, the 'method of causing the thin liquid-proofed strip the fold about the edge of the second strip which consists in winding the combined strips about a mandrel with the thin lining strip next to the mandrel, and guiding the edge of the marginal part which is to be folded about the edge of the second strip away from the mandel axis at the point at which the strip is moved tangentially onto the mandrel.

4. In the method defined in claim 1, a method consisting of spirally coiling a third paper strip outside the second spirally coiled strip and lapping the spirally abutting edges of the second strip, and leading said third strip longitudinally ontowthe coil of the second strip at a substantial angular distance around the coil beyond the point at which said second strip is led to the coil.

5. The method of making liquid-proofed spirally coiled paper tubing Which consists in feeding onto a mandrel at a suitably oblique angle to cause the successive coils of the spiral to abut edge to edge,a strip to form an inner body member, and a relatively thin and wider strip of liquid-proofed paper at the inner side of the first mentioned strip, With marginal portions of the excess width of said thin strip extending beyond the first mentioned strip at opposite edges of the latter; simultaneously feeding an outer body strip onto the mandrel at like oblique angle at angular distance around the mandrel beyond the point of tangency of the first strip and at a point in the length of the mandrel for positioning the coils of the outer strip lapping the spiral seam between the abutting edges of the consecutive coils of the first spiral; guiding the projecting marginal portion of the lining strip immediately antecedent to its running onto the mandrel to deflect said marginal portion outwardly with respect to the mandrel, and introducing an adhesive between the inner and outer body strips on their way to the mandrel.

6. A method of producing spirally coiled paper tubing consisting in simultaneously guiding obliquely onto a mandrel a relatively Wide and thin, and a relatively narrow and heavier paper strip with the thin wide strip next to the mandrel and the narrower strip next outside the thin strip with the marginal portions constituting the excess width of the thin strip extending laterally beyond the opposite edges of the narrower strip and causing one of said marginal portions to be deflected past the plane of the narrower strip immediately antecedent to the running ofthe strips onto the mandrel, and applying adhesive to the surface of the wide thin strip at the side toward the narrower strip in the movement of the strips toward and antecedent to their tangency to the mandrel.

7. In paper tube making, the method conl sisting in spirally coiling a wider liquidproofed strip and a narrower strip together about a mandrel with the liquid-proofed strip next to the mandrel and a marginal portion of the excess width of said wider strip at the side making obtuse angle with the mandrel extending in the plane of the contacting surfaces of the two strips past the correspending edge of the narrower strip., and with the angle of Obliquity of the course to the mandrel related to the width of the narrower strip to cause the consecutive coils of `said narrower strips about the mandrel to abut edge to edge when lodged on the mandrel; whereby the projecting marginal part of the liquid-proofed strip is flexed to extend between the abutting edges of the consecutive coils of the narrower strip and laid on the marginal portion of the outer surface of the abuttingr coil.

8. Inpapertubemaking,themethodconsisting in spirally coiling a wider liquid-proofed strip and a narrower strip together about a mandrel with the liquid-proofed strip next to the mandrel and a marginal portion of the excess width of said wider strip at the side making obtuse angle with the mandrel extending in the plane of the contacting surfaces of the two strips past the corresponding edge of the narrower strip, and with the angle of obliquity of the course to the mandrel related to the width of the narrower strip to cause the consecutive coils of said narrower strips about the mandrel to abut edge to edge when lodged on the mandrel, and causing a marginal portion of the excess width of the liquid-proofed strip at the side which makes an acute angle with the mandrel to be folded about the edge of the narrower strip as the strips run onto the mandrel, whereby the projecting marginal part of the liquid-proofed strip is flexed to extend between the abutting edges of the consecutive coils of the narrower strip and laid on the marginal portion of the outer surface of the abutting coil and onto the folded-over marginal portion of the liquid-proofed strip.

9. Spirally coiled paper tubing comprising a spirally coiled body member having its successive coils abutting edge to edge, in combination with a relatively thin and wider liquid-proofed lining strip coiled interiorly of the body member having a marginal portion of its excess width at one edge flexed outwardly past that edge of the body coil, and thereby extending through the spiral seam between the abutting edges of the consecutive coils of the body member.

10. Spirally coiled paper tubing comprising a spirally coiled body member having its successive coils abutting edge to edge, in combination with a relatively thin and wider i liquid-proofed lining strip coiled interiorly of the body member having. a marginal portion of its excess width at one edge flexed outwardly past that edge of the body coil, and thereby extending through the spiral seam between the abutting edges of the consecutive coils of the body member and lapped outlside the marginal portion of the adjacent coi 11. Spirally coiled paper tubing comprising a spirally coiled body member having its successive coils abutting edge to edge, in combination with a relatively thin and wider liquid-proofed lining strip coiled interiorly of the body member having a marginal portion of its excess width at one edge flexed outwardly past the corresponding edge of the body coil and folded back about that edge lapping on the outer surface of the marginal portion of said coil, and having a marginal portion of said excess width at the other edge exed outwardly past the other edge of the body member, and thereby extending through the spiral seam between the abutting edges of the consecutive coils of the body member in contact with the lirst mentioned marginal excess portion of the lining strip folded about the first mentioned edge.

In testimony whereof, I have hereunto set my hand at Chicago Heights, Ill., this 31st day of January, 1931.

RALPH P. BURTON. 

